A
Apoorva Devanshi
Guest
Globally, Climate change is causing an increase in extreme events, and developing nations like India are bearing the brunt of increased economic costs as well as higher death rates from natural disasters. As a result of which flooding incidents have increased in our country, including Chennai. According to reports, the recent flood which hit Chennai is worst in last 47 years. The primary worry, though is whether these previous flood incidents have taught us anything?! Have we taken any corrective actions?
India’s urban areas are particularly susceptible to flooding because of unplanned development, changing land use patterns, overpopulation, and an increase in natural disasters like storms, cyclones, and rising sea levels. Moreover, due to heavy rainfall and the presence of low-lying terrain in Chennai. The coastal districts in the Adyar basin frequently floods during the monsoon. The situation further gets worse due to poor drainage system, the encroachment of natural drainage systems like rivers and canals, and the formation of sand bars at river mouths.
Interestingly, in Ancient India we had traditional water- systems to prevent floods. Basically, all the rivers in Tamil Nadu are rainfed. So, several years ago Ancient Engineers devised a method to prevent floods- a series of cascading tanks. These tanks and reservoirs, also known as Eris were interconnected, community-based water supply systems. They channeled excess of water from rivers into reservoirs by incorporating the principle of rainwater harvesting. The cascading element used the topography to transport water up to 50 km in length. With just mud and labor—no concrete, no sophisticated machinery.
Ooranis on the other hand used to provide drinking water while Eris were used to irrigate fields. Compared to Eris, Ooranis are typically shallower and smaller. In order to collect rainwater and store it for later use, these tanks were made.
Now, it is one thing to conceptualize and build these structures; it is quite another to maintain their viability over the long run, as that depends entirely on how they are managed and maintained. Depending on the needs of the village, strategies were developed to hold the incoming water, with any extra flow being permitted to flow into the following tank in the series.
A devoted individual known as the “Neerkatti” was in charge of directing this water to specific fields and he kept a careful eye on the water level. To maintain the structural integrity of all the tanks, the entire village came together to undertake “Kudimaramathu,” or repair and maintenance work. But when the British arrived, everything changed.
These tanks once had a long history in South India. They once accounted for nearly 92% of all irrigation using tanks. By 1990’s this percentage dropped to almost 50%. Ten years later, in 2001, tank irrigation was estimated to have contributed just 5.18% of India’s total agricultural output. In sharp contrast, the percentage of water used from other sources, like borewells and tube wells, has been steadily increasing. (Source: Ministry of Agriculture, Government of India, New Delhi, Indian Agricultural Statistics Vol-I)
Due to urbanization and encroachment, many of these tanks are now rapidly disappearing. Many more are losing their storage capacity as a result of significant siltation. Over time, communities in Tamil Nadu have stopped performing the traditional “Kudimaramathu” ritual of cleaning and desilting their tanks before the monsoon. Our age old community based systems like “Eris Sangam,” or the tank federations, are also rapidly disappearing. More villagers actively participate in SHG activities than in tank federation’s due to lack of funds in the latter.
Thus, efforts need to be made by the government to revive our age old heritage water- systems. Such ancient marvels should be revived and built upon as they not only help in preventing floods but also help farmers by improving irrigation in a sustainable manner. Such tanks can help save approximately 365 hours or 45 working days per household (that is, the time spent to fetch water from neighbouring villages). Then being a community based system it instills a sense of belongingness among the people. Efforts should be made to protect this symbiotic relationship between the farmers and their water sources. Such ancient systems should be revived across all states for building climate resilience.
The post Reviving Ancient Water-Systems To Control Floods in Chennai ! appeared first on The Jaipur Dialogues.
Continue reading...
India’s urban areas are particularly susceptible to flooding because of unplanned development, changing land use patterns, overpopulation, and an increase in natural disasters like storms, cyclones, and rising sea levels. Moreover, due to heavy rainfall and the presence of low-lying terrain in Chennai. The coastal districts in the Adyar basin frequently floods during the monsoon. The situation further gets worse due to poor drainage system, the encroachment of natural drainage systems like rivers and canals, and the formation of sand bars at river mouths.
Eris and Ooranis of South India-
Interestingly, in Ancient India we had traditional water- systems to prevent floods. Basically, all the rivers in Tamil Nadu are rainfed. So, several years ago Ancient Engineers devised a method to prevent floods- a series of cascading tanks. These tanks and reservoirs, also known as Eris were interconnected, community-based water supply systems. They channeled excess of water from rivers into reservoirs by incorporating the principle of rainwater harvesting. The cascading element used the topography to transport water up to 50 km in length. With just mud and labor—no concrete, no sophisticated machinery.
Ooranis on the other hand used to provide drinking water while Eris were used to irrigate fields. Compared to Eris, Ooranis are typically shallower and smaller. In order to collect rainwater and store it for later use, these tanks were made.
Now, it is one thing to conceptualize and build these structures; it is quite another to maintain their viability over the long run, as that depends entirely on how they are managed and maintained. Depending on the needs of the village, strategies were developed to hold the incoming water, with any extra flow being permitted to flow into the following tank in the series.
A devoted individual known as the “Neerkatti” was in charge of directing this water to specific fields and he kept a careful eye on the water level. To maintain the structural integrity of all the tanks, the entire village came together to undertake “Kudimaramathu,” or repair and maintenance work. But when the British arrived, everything changed.
Present Scenario-
These tanks once had a long history in South India. They once accounted for nearly 92% of all irrigation using tanks. By 1990’s this percentage dropped to almost 50%. Ten years later, in 2001, tank irrigation was estimated to have contributed just 5.18% of India’s total agricultural output. In sharp contrast, the percentage of water used from other sources, like borewells and tube wells, has been steadily increasing. (Source: Ministry of Agriculture, Government of India, New Delhi, Indian Agricultural Statistics Vol-I)
Due to urbanization and encroachment, many of these tanks are now rapidly disappearing. Many more are losing their storage capacity as a result of significant siltation. Over time, communities in Tamil Nadu have stopped performing the traditional “Kudimaramathu” ritual of cleaning and desilting their tanks before the monsoon. Our age old community based systems like “Eris Sangam,” or the tank federations, are also rapidly disappearing. More villagers actively participate in SHG activities than in tank federation’s due to lack of funds in the latter.
Way Forward-
Thus, efforts need to be made by the government to revive our age old heritage water- systems. Such ancient marvels should be revived and built upon as they not only help in preventing floods but also help farmers by improving irrigation in a sustainable manner. Such tanks can help save approximately 365 hours or 45 working days per household (that is, the time spent to fetch water from neighbouring villages). Then being a community based system it instills a sense of belongingness among the people. Efforts should be made to protect this symbiotic relationship between the farmers and their water sources. Such ancient systems should be revived across all states for building climate resilience.
The post Reviving Ancient Water-Systems To Control Floods in Chennai ! appeared first on The Jaipur Dialogues.
Continue reading...